Effect of internal mass in the lattice Boltzmann simulation of moving solid bodies by the smoothed-profile method

A computational method for the simulation of particulate flows that can efficiently treat the particle-fluid boundary in systems containing many particles was developed based on the smoothed-profile lattice Boltzmann method (SPLBM). In our proposed method, which we call the improved SPLBM (iSPLBM), for an accurate and stable simulation of particulate flows, the hydrodynamic force on a moving solid particle is exactly formulated with consideration of the effect of internal fluid mass. To validate the accuracy and stability of iSPLBM, we conducted numerical simulations of several particulate flow systems and compared our results with those of other simulations and some experiments. In addition, we performed simulations on flotation of many lightweight particles with a wide range of particle size distribution, the results of which demonstrated the effectiveness of iSPLBM. Our proposed model is a promising method to accurately and stably simulate extensive particulate flows

A Highly Antibacterial Achievement of Hollow Fiber Polyethersulfone (PES) Membrane Loaded with Silver Nanoparticles

A highly antibacterial of hollow fiber polyethersulfone (PES) membrane was prepared by loading silver nanoparticles within the PES graft acrylamide (AAm)-membrane. The grafted layers of AAm were provided the matrix for silver nanoparticles (AgNPs) entrapment. The characterization of the prepared hollowfiber (HF) PES membrane loaded with silver nanoparticles were examined by using transmission electron microscopy (TEM). To examine the antibacterial property of the prepared AgNPs-AAm-PES membrane, the halo zone and the shaking flask test were carried out. In these tests, both of unmodified PES membrane and AgNPs-AAm-PES membrane were exposed to pure culture suspension of Escherichia coli (E. Coli) bacteria with the concentration of 107 CFU/ml. The viable bacteria formed within the membrane surfaces and themembrane circumferences were observed by the halo zone formation, while the percentage of bacteria killing ratio was determined by shaking flask test method. The TEM results showed that the silver nanoparticles were formed within grafted layers of AAm-PES membrane and the size of silver nanoparticleswere about 10 nm. The AgNPs-AAm-PES membrane were highly effective to prevent the membrane biofouling as shown by the clearly halo zone formation compared with the unmodified PES membrane. The shake flask test were also revealed that almost 99.9 percent of the E. coli bacteria were killed when theyhaving exposed to the AgNPs-AAm-PES membrane. This was due to the silver ions are allowed to release from its membrane surfac

Effect of Polymeric Additives on the Performances of Polyethersulfone Blend Hollow Fiber Membrane

The article reported the preparation and modification of hydrophobicpolyethersulfone (PES) by blending the solution with hydrophilic additives Tetronic 304, Tetronic 704, Tetronic 1307, and Tetronic 908. Polymeric porous membranes are generally prepared by the phase separation of polymer solution. In this work, we prepared hollow fibre membrane by non-solvent induced phase separation (NIPS). Effect of molecular weight of surfactant added on the performance and characteristic of fabricated membrane were investigated. The control PES membrane has the highest contact angle, indicating thelowest hydrophilic. With addition of surfactant Tetronic in the polymer blend hollow fibre membrane, the water contact angle decreased indicates that the membrane surface is more hydrophilic. Scanning electron microscopy (SEM) images for all of the membrane showed the structure of fibre with finger-like macro voids through the cross-section. The sponge-type of structure in the centre path of original membrane was disappearing with addition of Tetronic. Ultrafiltration experiment results showed that water permeability washighest with addition of Tetronic with lowest molecular weight. According to thecharacteristics of resulting membrane such as hydrophilicity, ultrafiltration performance, and pores structure, surfactant Tetronic was a good additive to produce hydrophilic membrane for drinking water applicatio

Antifouling Double-Skinned Forward Osmosis Membranes by Constructing Zwitterionic Brush-Decorated MWCNT Ultrathin Films

Pressure retarded osmosis (PRO) process is hindered by severe fouling occurring within the porous support of the forward osmosis (FO) membranes. We designed a novel double-skinned FO membrane containing a polyamide salt-rejecting layer and a zwitterionic brush-decorated, multiwalled carbon nanotube (MWCNT/PSBMA) foulant-resisting layer on the back side. Our results demonstrated that the coating of the MWCNT/PSBMA layer on the porous polyketone (PK) support imparted enhanced hydrophilicity and smaller membrane pore size, thereby providing excellent resistance toward both protein adhesion and bacterial adsorption. We also further evaluated this resultant double-skinned membrane (i.e., TFC-MWCNT/PSBMA) in dynamic PRO fouling experiments using protein and alginate as model organic foulants. Compared to the pristine TFC-PK and hydrophobic TFC-MWCNT membranes, the TFC-MWCNT/PSBMA membrane exhibited not only the lowest water flux decline but also the highest water flux recovery after simple physical flushing. These results shed light on fabrication of antifouling PRO membranes for water purification purposes

血漿ADAMTSは肝硬変患者の予後をChild-PughスコアやMELDスコアと同様に生存率を予測できる可能性がある

Aim:  Decreased plasma ADAMTS13 activity (ADAMTS13:AC) results in accumulation of unusually large von Willebrand factor multimers and platelet thrombi formation. Our aim was to evaluate whether ADAMTS13:AC is a prognostic marker in patients with liver cirrhosis. Methods:  Plasma ADAMTS13:AC and its related parameters were examined in 108 cirrhotic patients. Results:  ADAMTS13:AC decreased as the severity of liver disease increased (means: controls 100%, Child A-cirrhotics 79%, Child B-cirrhotics 63%, and Child C-cirrhotics 31%). ADAMTS13:AC markedly decreased in the cirrhotics with hepatorenal syndrome, refractory ascites and hepatic encephalopathy. The cumulative survival time was the shortest (median: 4.5 months) in the cirrhotics with severe to moderate ADAMTS13:AC deficiency (50%). In contrast, based on the Child-Turcotte-Pugh (CTP) score, Child C-cirrhotics had the worst survival, but the survival probabilities did not differ between Child A and B cirrhotics. Based on the Model for End-Stage Liver Disease (MELD) score, the survival was the worst for the cirrhotics in the fourth quartile, but it was not different among cirrhotics in the first three quartiles. Cox proportional-hazards regression analysis showed that ADAMTS13:AC and serum albumin were independent factors affecting the survival. Conclusions:  ADAMTS13:AC concomitantly decreases as the functional liver capacity decreases. This activity may be a useful prognostic marker that is equal or superior to the CTP score and the MELD score to predict not only the short-term prognosis but also the long-term survival of the cirrhotic patients.博士（医学）・甲613号・平成26年3月17

Drying colloidal systems: laboratory models for a wide range of applications

The drying of complex fluids provides a powerful insight into phenomena that take place on time and length scales not normally accessible. An important feature of complex fluids, colloidal dispersions and polymer solutions is their high sensitivity to weak external actions. Thus, the drying of complex fluids involves a large number of physical and chemical processes. The scope of this review is the capacity to tune such systems to reproduce and explore specific properties in a physics laboratory. A wide variety of systems are presented, ranging from functional coatings, food science, cosmetology, medical diagnostics and forensics to geophysics and art

Effect of the Characteristic Properties of Membrane on Long-Term Stability in the Vacuum Membrane Distillation Process

Membrane distillation (MD) is a technology that can treat feed solutions with higher osmotic pressure, as well as produce high-purity water. However, the water production cost of the MD process is expensive. In this study, to decrease the water production cost, we attempted to evaluate the effect of membrane characteristics on the long-term stability of a vacuum MD (VMD) system. We fabricated four different types of polyvinylidene difluoride hollow fiber membranes, and operated a VMD system with 3.5 wt% NaCl aqueous solution at 65 °C as a feed under 11 kPa of air gap pressure. Consequently, in the proposed VMD system, it is found that the liquid entry pressure (LEP) is the most important factor. When LEP was higher than 0.37 MPa, the pilot-scale module was very stable for long-term operations, and the vapor flux was approximately 19.3 kg/m2·h with a total salt retention factor of over 99.9% during the 300-h operation